One of the salient features of the present system, which operates with horizontal discharge molding machines, such as shown in the present assignee's U.S. Pat. Nos. 4,260,352 and 4,235,580, both of which I incorporate completely herein by reference, is the treatment of the upper surfaces of the stones or products from above while the products move continuously in horizontal disposition on the molding machine discharge conveyor or an extension thereof. The texturizing which occurs is performed on the so-called "green" products before any curing takes place.